Heat carbonizable embroidery crinoline and method of making the same



United St tes PatentO 2,741,569 HEAT CARBONIZABLE El't/IBROIDERYCRINOLINE AND METHOD OF MAKING T SAME Ralph E. Stanford, West Medway,Mass., assignor to The Kendall Company, Boston, Mass, a corporation ofMassachusetts N Drawing. Application November 14, 1952, Serial No.320,613

7 Claims. (Cl. 117-143) This application relates to normally stable, yetreadily heae'car'bonizable, cellulosic fabrics and methods of making thesame, more particularly to so-called embroidery crinoline. Su'chcrinoline is pinned to sleazy fabrics, such as lightweight silks andrayons as a temporary support to enable the fabrics to be maneuveredreadily under a stitching needle. After the embroidery is completed, theassembly is heated in an oven or with aflat iron to carbonize thecrinoline to the extent that light brushing will sufiice to remove itfrom the embroidered fabric. Obviously the crinoline must carbonize andcrumblerat a temperature which will not cause any appreciable damage tothe embroidered fabric.

Embroidery crinoline is usually prepared by impregnating a starched,openmesh, cotton fabric with dilute sulfuric acid. The acid-impregnatedfabric is so susceptible to destruction by heat that continuous dryingis not feasible unless done at .uneconomically low temperatures andspeeds. .Even at ordinary room temperatures the embroidery crinoline soprepared deteriorates so rapidly that in as short a time as 24 hours itmay .be too weak for use. .Because of the impediments tocontinuousprocessing-and the very short shelf life of theproduct, thetrade h'as beengenerally forced toprepare its own embroidery crinoline.Not only is the small-batch method tineconoiiiical and cumbersome forthe embroiderenbut it is also highly wasteful of his time and materials.if he'has prepared too much crinoline for the da s business, he mustthrow"it away,because it will be too weak for use on the following day;If hehas pr'epared roe 1iitle,he must hold 'uphis "embroider work untiladditional crinolinefhas been prepared.

"It is the primar object o'f'this; invention to provide an embroidery"cri'noline which is highly resistant to deterioration fo'r long periodsor time at 'or'dinary temperatu'res, yet readily "carbohiiable atmoderately elevated temperatures, such as are used in'the embroideryfrade.

A further object of this invention isto supply a'me'tho'd of, preparingembroidery crinoline which makes possible rapid commercial drying.

Despite the di'fiiculties apparent in fulfilling these seeminglyconflicting requirements, "I have discovered and provided for the thefirst time inthea'rt'an "embroidery crinoline with a sheli life of atleast'four months yet readily catbonizable-by the usualpost-embroidering heat treatments. My invention involves the treatmentof a cellulose fabric withan acid-forming salt selected from the groupconsisting or aluminum chloride, aluminum sulfate, and mixtures thereof;an alkaline retarder; and astitieningagent; the acid-for-ming salt beingsubstantially in excess of the alkaline retarder 'on an equivalentweight basis.

":By the :te'rm cellulose I mean to include natural 2,741,569 PatentedApr. 10, 1956 2 erated cellulose, whether 'of the viscose ofc'upra'inrnonium type. k

For the purposes of this application, alkaline retarder is defined asany potentially alkaline substance, such as the salt of a strong baseand a weak acid, or a water insoluble inorganic base, which willneutralize free acid but not interact 'with the acid-forming salt to anyappreciable extent at ordinary temperatures and humidities. Typical ofthe wide variety of alkaline retarders which may be used are sodium andpotassium salts of acetic, carbonic, and boric acid and iron and zinchydroxides.

I normally use starch as the stiffening agent for my embroiderycrinoline because it is cheap and readily available, but any of thecommon rigidizing substances may be employed such as, polyvinyl alcohol,polyvinyl acetate, sodium alginate, and carboxymethyl cellulose.

The concentration of the acid-forming salt must be sufiiciently inexcess of the concentration of the alkaline retarder to readilycarbonize the cellulose fabric during the post-embroidery heattreatment. For reasons of economy I prefer to employ relatively lowconcentrations of both the acid-forming salt and the alkaline retarder.l have found that the weight-equivalent percentage excess ofacid-forming salt should be within the range of 0.01%

, to 0.4% based on the air-dry weight of fabric plus stiffencellulose"such as cotton, linen, and estate, and regent ing agent and preferablybetween 0.03% and 0.1%. The weight-equivalent percentage excess may becalculated by subtracting the number of pound equivalents of alkalineretarder from the number of pound-equivalents of acid-forming salt anddividing this result by the weight in pounds of the stiffened fabric,and multiplying by 100. The weight-equivalent percentage of alkalineretarder, based on the stiffened fabric, should be atleast 0.001%, andthe ratioon an equivalent weight basis, of acid-forming salt to alkalineretarder preferably between S to 1 and 10 to 1.

with a solution of the acid-forming salt, squeezed to femove excess,impregnant and dried. While, in general, the order of applying theingredients may .be varied and any combination of the ingredientsapplied simultaneously, the following considerations should be takeninto account. Ingredients which are incompatible in the same solutionshould obviously be separately applied :to the fabric. The separateapplication of the acid-forming salt and the stiffening agent isdesirable for the dude pendent reason thatit is commercially convenientto dry fabrics impregnated with aqueous stifi'ening solutions atrelatively high temperatures. It the acid-forming salt is present in thefabric at this stage, there issome danger that the fabric maybecomeprematurely degraded. To avoid this same danger'I prefer to applythe acid-forming salt to the fabric/in the final padding step :sothatthe salt will be present in the fabric during only one drying operation.It is also highly desirable that the alkaline retarder be applied .tothe fabric prior to, or simultaneously with, the acid-forming salt'because of the protection to sthe fabric afforded bythe retarder duringthe drying. In any event, it is preferable to dry the acid-salt treatedfabric at temperatures below 200 F., and in-the absence-of alkalineretarder, below F. In both cases care should be taken to avoido'verdrying. As "illustrative of my invention, but not in limitationthereof, the following examples are given.

Example I 28 x 24 bleached cotton gauze was passed through a two-dipstarch pad containing the following formulations:

Second pad:

40 gals. starch solution prepared by boiling a mixture of 94 lbs.thin-boiling starch and 17 gals. water 1.52 lbs. anhydrous sodiumacetate After drying, the treated fabric was padded with the 7 followingsolution:

60 lbs. aluminum chloride (aqueous solution-S% AlCl3-6H2O) 55 gals.water 350 grams Triton X-100, a non-ionic wetting agent distributed byRohm & Haas Company. and stated to be the iso-octyl ether ofpolyethylene glycol.

Example 2 32 x 28 bleached cotton gauze was passed through a single dipstarch pad containing the following formula tion:

36 gallons starch solution prepared by boiling a mixture of poundscornstarch, pounds thin-boiling starch and 17 gallons water.

0.87 pound anhydrous potassium acetate After drying, the treated fabricwas padded with the following solution:

91.5 poundsaluminum sulfate-Al2(SO4)a18H2O 55 gallons water 350 gramsnon-ionic wetting agent The squeezed impregnated fabric was dried as inExample 1. The weight-equivalent percentages of acidforming salt andalkaline retarder were 0.1050% and 0.0080%, respectively, representingan acid-forming salt excess of 0.097%.

Example 3 The procedure of Example 1 was followed except that theacid-forming salt solution consisted of:

38 lbs. aluminum chloride (aqueous solution-40% AlCl3-6H2O) 54 lbs.aluminum sulfate--Alz(SO4)a-18H2O 55 gals. water The weight-equivalentpercentages of acid-forming salt and alkaline retarder were 0.0685% and0.0077%, respectively, representing an acid-forming salt excess of0.0608%.

4' Example 4 28 x 24 unbleached cotton gauze was treated according tothe procedure of Example 1 except that the following was substituted forthe first pad formulation:

First pad:

32 gals. starch solution prepared by boiling a mixture of 10 lbs.cornstarch, lbs. thin-boiling starch and 17 gals. water 1.29 lbs.anhydrous sodium acetate Example 5 32 x 28 bleached cotton gauze waspadded with a starch solution consisting of:

25 lbs. cornstarch 25 lbs. thin-boiling starch 5.8 lbs. sodium acetate12.0 gals. water After drying the treated fabric was impregnated withthe following solution:

34.6 lbs. aluminum chloride (aqueous solution-50% AlCls-6H2O) 95.4 lbs.aluminum sulfateAl2(SO4)3l8H2O 18 gals. Water The fabric was dried as inExample 1. The weight equivalent percentages of acid-forming salt andalkaline retarder were 532% and .143%, representing an acidforming saltexcess of 389%.

In my treated materials, in addition to the applied ingredients, thereis necessarily present some water in the form of moisture regain of thecellulose and as water of hydration of some or all of the otheringredients. I am not aware of the precise chemical state of the variousconstituents in my treated cellulose materials nor the exact manner inwhich these constituents interact at elevated temperatures. Although myinvention is not dependent upon any particular theory of operation, themost plausible explanation of the remarkable performance of my novelmaterials is that any free acid evolved by the acid-forming salt priorto the intentional carbonization of the yarns or fabric is absorbed bythe alkaline retarder. It is believed that the acid-forming salts of myinvention, unlike free acids and most acid-forming substances, can beused in concentrations effective to carbonize the cellulose at elevatedtemperatures without evolving free acid at ordinary temperatures inexcess of that amount which can be absorbed or neutralized by thealkaline retarder. Regardless of the correctness of this theory, I havefound that the alkaline retarder does serve to protect the fabric frompremature degradation, both during the drying operation or operations inthe preparation of my specially treated materials and during storage ofthe finished products before use.

In the appended claims, the description of the embroidery crinoline asnormally stable is intended to mean that the crinoline has a shelf-lifeof at least one month at ordinary temperatures and humidities.

I claim:

1. As a new article of manufacture, a normally stable yet readilyheat-carbonizable embroidery crinoline comprising a cellulosic fabricimpregnated with a textile stiffening agent for said fabric, an alkalineretarder selected from the group consisting of water insoluble inorganicbases and water soluble salts of weak acids and strong bases, thealkaline retarder having the characteristics of being able to neutralizefree acid and not interact with acid-forming salt to any appreciableextent at ordinary temperatures and humidities, the weight equivalentpercent of said alkaline retarder being between 0.001 and 0.143% basedon the weight of said stiffened fabric, and an acid-forming saltselected from the group consisting of aluminum chloride, aluminumsulfate and mixtures thereof, the weight equivalent percent excess ofsaid acid salt over said alkaline retarder being between 0.01% and 0.4%based on the weight of the stiffened fabric.

2. The embroidery crinoline according to claim 1 in which the ratio ofacid-forming salt to alkaline retarder is between 5 to 1 and 10 to 1 onan equivalent weight basis.

3. The embroidery crinoline according to claim 1 in which the alkalineretarder is sodium acetate.

4. The embroidery crinoline according to claim 1 in which the cellulosefabric comprises cotton.

5. A process for preparing a normally stable yet readilyheat-carbonizable embroidery crinoline which comprises applying to acellulose fabric from at least one aqueous solution a textile stiffeningagent for said fabric, an alkaline retarder selected from the groupconsisting of water insoluble inorganic bases and water soluble salts ofweak acids and strong bases, the alkaline retarder having thecharacteristic of being able to neutralize free acid while notinteracting with acid-forming salt to any appreciable extent at ordinarytemperatures and humidities, and an acid-forming salt selected from thegroup consisting of aluminum chloride, aluminum sulfate and mixturesthereof, and drying said fabric after each application of solution, thealkaline retarder being present in an amount such that the equivalentweight percent of said alkaline retarder is between 0.001% and 0.143%based on the weight of the stiifened fabric and the weight equivalentpercent excess of acid-forming salt over said alkaline retarder beingbetween 0.01% and 0.4% based on the weight of the stiffened fabric.

6. The process according to claim .5 in which the drying is performed ata temperature in excess of 150 F. 7. The process of preparing a normallystable yet readi- 1y heat-carbonizable embroidery crinoline whichcomprises applying to a cellulosic fabric a textile stiffening agent forsaid fabric and an aqueous solution of an alkaline retarder saidalkaline retarder being selected from the group consisting of waterinsoluble inorganic bases and water soluble salts of strong bases andweak acids, the alkaline retarder having the characteristic of beingable to neutralfree acid while not interacting with acid-forming salt toany appreciable extent at ordinary temperatures and humidities, saidalkaline retarder being in an amount between 0.001% and 0.143% based onthe Weight of the stiffened fabric, drying said fabric, applying to saidfabric an aqueous solution of anacicl-forming salt selected from thegroup consisting of aluminum chloride, aluminum su1- fate and mixturesthereof, in an amount sufiicient to deposit a weight equivalent percentexcess of acid-forming salt over alkaline retarder of between 0.01% and0.4%, and drying said fabric.

References Cited in the file of this patent UNITED STATES PATENTS917,402 Bauer Apr. 9, 1909 1,425,520 Giesler Aug. 15, 1922 1,513,370Cadgene Oct. 28, 1924

1. AS A NEW ARTICLE OF MANUFACTURE, A NORMALLY STABLE YET READILYHEAT-CARBONIZABLE EMBROIDERY CRINOLINE COMPRISING A CELLULOSIC FABRICIMPREGNATED WITH A TEXTILE STIFFENING AGENT FOR SAID FABRIC, ANDALKALINE RETARDER SELECTED FROM THE GROUP CONSISTING OF WATER INSOLUBLEINORGANIC BASES AND WATER SOLUBLE SALTS OF WEAK ACIDS AND STRONG BASES,THE ALKALINE RETARDER HAVING THE CHARACTERISTICS OF BEING ABLE TONEUTRALIZE FREE ACID AND NOT INTERACT WITH ACID-FORMING SALT TO ANYAPPRECIABLE EXTENT AT ORDINARY TEMPERATURES AND HUMIDITIES, THE WEIGHTEQUIVALENT PERCENT OF SAID ALKALINE RETARDER EBING BETWEEN 0.001 AND0.143% BASED ON THE WEIGHT OF SAID STIFFENED FABRIC, AND AN ACID-FORMINGSALT SELECTED FROM THE GROUP CONSISTING OF ALUMINUM CHLORIDE, ALUMINUMSULFATE AND MIXTURES THEREOF, THE WEIGHT EQUIVALENT PERCENT EXCESS OFSAID ACID SALT OVER SAID ALKALINE RETARDER BEING BETWEEN 0.01% AND 0.4%BASED ON THE WEIGHT OF THE STIFFENED FARBIC.